The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 08, 2011
Filed:
Feb. 18, 2009
Applicants:
Yasunori Suzuki, Yokohama, JP;
Shoichi Narahashi, Yokohama, JP;
Inventors:
Yasunori Suzuki, Yokohama, JP;
Shoichi Narahashi, Yokohama, JP;
Assignee:
NTT DoCoMo, Inc., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03F 1/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
In a feedforward amplifier () including a signal cancellation circuit () and a distortion eliminating circuit (), a harmonic reaction amplifier () is used as a main amplifier of the signal cancellation circuit. A controller () obtains an adjacent channel leakage power ratio (ACLR) and a power efficiency from an output of the feedforward amplifier () and controls the gate bias voltages of two transistors (A andB) of the harmonic reaction amplifier () to maximize the power efficiency under the condition that the ACLR is less than or equal to a reference value.